I stumbled upon this article from about a year ago. At first, I thought the headline sounded awful...from a printer's viewpoint anyway! But after reading through it, I found the content to be quite helpful; it will certainly influence my own business card exchanges in the future:

"Don't expect too much when handing out business cards...

by Greg Peters

Networking, like so many other pursuits has its own set of first-timer mistakes. If you are new to the practice, watch out for these misconceptions and you'll end up having an easier time of it. Today's mistake? Unrealistic business card expectations.

When I first started networking, I would show up at the event — the chamber networking lunch, for example. I would do the best I could, mixing and mingling with the other attendees. I would get so excited when, after chatting for a few minutes, someone would ask me for one of my business cards.

Of course, I would present them with my card (sometimes two!) and then I would return home with the glow of success all about me. Yes, sir, things were really about to take off! For the next several days, I would look forward with anticipation to their call.

Of course, no one ever (and I mean ever) called.

...

Remember that the most valuable card at the networking event is the one you get from someone else."